Science of Synthesis

Li, W-R., Science of Synthesis, (2005) 21, 221.

A copper(I)-mediated enamide formation technique can be used to synthesize highly unsaturated enamide side chains of natural products. The reaction occurs at moderate temperatures and the method is suitable for the attachment of potentially labile enamide chains to complex substrates.[‌212‌] In the amidation reaction, vinyl iodides are more reactive than vinyl bromides as substrates; however, in the coupling reaction with benzamide, when an excess of (E)-1-iodohept-1-ene (2.2 equiv) and cesium carbonate (2.0 equiv) are used, the enamide ‌173‌ (77% yield) is the sole product (‌Scheme 41‌). N,N-Divinyl amide products do not form in this reaction and the excess iodoalkene (70%) is recovered. Reaction of conjugated amide ‌174‌ under similar conditions gives N-substituted amide ‌175‌ in 69% yield. In addition, the copper(I)-catalyzed vinylic substitution protocol, which complements related C—N bond-formation methodologies, follows a stereocontrolled pathway.

‌Meeeee 88‌ Meeeeeeeeee ee M-Meeee Meeeee ee Meeeee(M)-Meeeeeeee Meeeeeeee[‌888‌]

Meeeeeeeeeee Meeeeeeee

(8M,8M)-M-[(8M)-Meee-8-ee-8-ee]eeee-8,8-eeeeeeeee (‌888‌); Meeeeee Meeeeeeee:[‌888‌]

(8M,8M)-Meee-8,8-eeeeeeeee (‌888‌; 88 ee, 8.88 eeee), eeeeee(M) eeeeeeeee-8-eeeeeeeeeee (88.8 ee, 8.88 eeee), eee Me8MM8 (888 ee, 8.88 eeee) eeee eeeeee ee ee eeee-eeeee 88-eM Meeeeee eeeee eeeeeeee eeee e eeeeeee eee. Meeee MMM (8 eM) eee eeeee eeee ee eeee-eeeee eeeeeee. Mee eeeeeeeeee eee eeeeeeee eeeee e eeee eeeeee eeeee eee eeeeeeeee eeeeee. (M)-8-Meeeeeee-8-eee (888 ee, 8.8 eeee, 88 μM) eee eeeee ee eee eeeee ee eeeee e eeeeeeeeee eeeeeee. Mee eeeeeee eee eeeeeeee eeeee eeeee e eeee eeeeee eeeee ee eeeeeee eee eeeeeeeee eee eeeeeeee eee eee eeeeeeeeee eee eeeeeee ee 88 ºM eee 88 e eeeee eeeee. Mee eee eeeeee eee eeeeee ee ee, eeeeeee eeee Me8M, eee eee Me8M eeeeeeee eeee eeeeee eeee eM 8 eeeeee. Mee eeeeeee eeeee eee eeeeeeeee eeeee eeee eeee Me8M. Mee eeeeeeee eeeeeee eeeeee eeee eeeee (Me8MM8) eee eeeeeeeeeeee. Mee eeeeeee eee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee, 8% Me8M ee eeeeeee/MeMMe 8:8) ee eeee e eeeee eeeee; eeeee: 88 ee (88%); ee 888–888°M.

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) M 8-8, 8888.